Basics
Description
- Scoliosis: lateral curvature of spine exceeding 10 degrees on PA full-spine radiograph (with rotation of spine); curves <10 are termed spinal asymmetry; considered idiopathic only after other causes have been excluded
- Kyphosis: anteriorly concave curvature of vertebral column
Epidemiology
- Female-to-male ratios:
- 1.4:1 for curves 11 " 20 degrees
- 5.4:1 for curves >20 degrees
Prevalence
- Generally considered 1.5 " 3% for curves ≥10 degrees
- 0.3 " 0.5% for curves >20 degrees
Risk Factors
Genetics
Positive familial history for idiopathic scoliosis in 30% (not predictive of severity)
- Under active investigation: GWAS and whole exome sequencing studies
- Several candidate genes have been identified.
Etiology
By definition, unknown; listed are some theories, none proven in isolation:
- Genetic
- Positive familial history for scoliosis in 30% (not predictive of severity)
- Connective tissue disorder
- Associated with several connective tissue disorders (including Marfan syndrome, Ehlers-Danlos syndrome, etc.)
- Alterations in connective tissue of the spine, paraspinous muscles, and platelets
- May be related to osteopenia (decreased bone mineral density) of vertebral bodies
- Neurologic (equilibrium system)
- Abnormalities noted in vestibular, ocular, proprioceptive, and vibratory functions
- Hormonal
- Lower levels of melatonin secreted from pineal body in those with adolescent idiopathic scoliosis
- Growth hormone: more of an influential factor than an etiologic factor in studies
- Vertebral growth abnormalities
- Asymmetric growth rates between the right and left sides of the spine
Commonly Associated Conditions
- Connective tissue disorders, including Marfan syndrome and Ehlers-Danlos syndrome
- Neurofibromatosis
- Neuromuscular conditions, including cerebral palsy, spina bifida, spinal muscular atrophy, Friedreich ataxia, etc.
- If any of these conditions are present, the diagnosis is no longer idiopathic.
Diagnosis
History
- Onset: Consider when first noted, by whom, rate of worsening, previous treatment, patient recent growth, the physical change of puberty, associated signs or symptoms, familial history, etc.
- Patients with idiopathic scoliosis usually should not have pain, although they might have a discomfort or mild pain.
- Back pain in scoliotic patients must be investigated thoroughly and taken seriously.
- If night pain, consider tumor such as osteoid osteoma.
Physical Exam
- General inspection to look for skin changes such as cafe au lait spots, pigmentation, or other signs of neurofibromatosis; also dysraphic signs (e.g., hairy patches, midline hemangioma, skin dimpling)
- Assess for skeletal maturity, hyperelasticity, contracture, congenital anomalies.
- Assess for deformity; asymmetry of spine, shoulders, waist, and trunk, including decompensation; abnormalities of thoracic kyphosis or cervical or lumbar lordosis; disfigurement of the torso; or rib rotation.
- Adams forward bend test used to look for rib or paraspinous elevations
- Assess for leg length discrepancy, congenital anomalies, and neurologic abnormalities (including abnormal abdominal reflex).
- Special finding:
- Crankshaft phenomenon
- Progression of curve size and rotation following posterior spinal fusion in a young child, result of continued anterior spinal growth
- Patient is Risser 0, open triradiate cartilages, <10 years old, and prior to occurrence of peak height velocity (time of maximum spinal growth).
- Consider anterior fusion in addition to posterior fusion.
- Physical exam tricks:
- Measure angle of trunk rotation with scoliometer.
- Abnormal abdominal reflex may suggest intraspinal pathology, including syrinx.
- Perform Adams forward bend test after the pelvis is leveled by inserting appropriately sized block underneath the short leg in patients with scoliosis and leg length discrepancy.
Diagnostic Tests & Interpretation
Pulmonary function testing is useful preoperatively for more severe curves.
Lab
Usually not helpful unless to rule out associated metabolic conditions
Imaging
- Plain standing posterior " anterior and lateral scoliosis films on long 3-foot radiograph cassette or 3-D low-dose radiation system
- One must look for soft tissue and congenital bony abnormalities (Wedge vertebrae, bars, hemivertebrae).
- Curve is measured using Cobb method.
- The status of the triradiate cartilage and Risser classification of iliac apophysis ossification are indicators of maturity.
- The triradiate cartilage usually closes before the iliac apophysis appears (Risser 0).
- Risser sign is defined by the amount of calcification present in the iliac apophysis and measures the progressive ossification from anterolaterally to posteromedially.
- A Risser grade of 1 signifies up to 25% ossification of the iliac apophysis, proceeding to grade 4, which signifies 100% ossification.
- A Risser grade of 5 means the iliac apophysis has fused to the iliac crest after 100% ossification.
- Risser grade (0 " 5) gives an estimate of how much skeletal growth remains and is correlated with risk of curve progression.
- MRI is not routinely necessary for adult idiopathic scoliosis without back pain.
- 7% prevalence of intraspinal abnormalities are found in left thoracic curves, so MRI maybe indicated.
- Curve patterns are classified according to King or Lenke classifications.
- Renal ultrasound is used for evaluation of patient with congenital scoliosis (look for associated renal abnormalities).
Differential Diagnosis
- Adolescent idiopathic scoliosis (11 " 17 years)
- Juvenile idiopathic scoliosis (4 " 10 years)
- Infantile idiopathic scoliosis (0 " 3 years)
- Congenital scoliosis " due to bony abnormalities of the spine that are present at birth (failure of formation or segmentations of vertebrae)
- Scoliosis associated with neurofibromatosis
- Scoliosis associated with tumors (e.g., osteoid osteoma)
- Neuromuscular scoliosis (e.g., cerebral palsy, spina bifida, muscle disorders)
- Postural scoliosis (e.g., from leg length discrepancy)
- No rib hump or rotation
- Does not have fixed deformities
- Disappears with forward bending
- Long curve
- No progression
Treatment
General Measures
- Treatment
- Concepts for treatment are based on severity of deformity and on likelihood of progression.
- Observation
- Curves <25 degrees
- Immature patients (Risser 0, 1, 2) should be reevaluated in 4 " 6 months.
- Skeletally mature patients (Risser 4 or 5) usually do not require ongoing follow-up unless special circumstances exist.
- Curves 25 " 45 degrees in skeletally mature patients
- Risser 4 or 5 patients are usually reevaluated in 6 months to 1 year.
- Mature patients are usually reevaluated yearly.
Additional Therapies
- Brace treatment
- Curves 25 " 45 degrees (Risser 0, 1) and 30 " 45 degrees (Risser 2 or 3)
- Brace on initial evaluation.
- Curves ≥25 degrees (in Risser 0 " 3 patient) that have demonstrated >10 degrees progression during period of observation
- Continue brace treatment until maturity (2 years postmenarchal and Risser 4 in females, Risser 5 in males).
- Brace types
- Thoracolumbosacral orthosis (TLSO): success reported when used >16 " 18 hours daily; significantly improved outcome when compared with natural history
- Cervicothoracolumbosacral orthosis (CTLSO): seldom needed except for higher thoracic or cervical curves
- Nighttime bending brace
Surgery/Other Procedures
- Recommended when curves exceed 45 " 50 degrees
- Exception: Balanced thoracic and lumbar curves <55 degrees may be observed for progression.
- Thoracic curves and double major curves
- Posterior segmental fixation instrumentation remains current state of the art.
- Anterior spinal instrumentation for selected curves
- Isolated thoracolumbar and lumbar curves
- Anterior spinal fusion using solid rod segmental constructs
Ongoing Care
Follow-up Recommendations
Patient Monitoring
- Watch for back pain associated with idiopathic scoliosis (may indicate other diagnosis):
- Present in 23% at time of initial evaluation (additional 9% during follow-up)
- Of those with back pain, only 9% found to have identifiable cause such as spondylolysis, Scheuermann, syrinx, disc herniation, tumor, tether cord.
Prognosis
- Overall, good for most patients
- Risk of curve progression related to patient 's maturity (Risser sign, menarcheal status) and to size of curve
- Curves <20 " 25 degrees have low risk of progression, even if patient is immature.
- Curves 25 " 45 degrees have higher risk of progression, particularly in skeletally immature patients.
- Curves >45 " 50 degrees have much higher risk of progression, regardless of maturity.
Complications
Natural history:
- Reduced pulmonary function for patients with thoracic curves >60 degrees
- Progression of lumbar curves >50 degrees in adult life with degenerative disc disease and pain in some
- Cosmetic and emotional issues
- Complications of brace use include skin irritation, discomfort, and noncompliance.
- Surgical complications are usually more severe, including infection, instrumentation loosening or breakage, neurologic damage, paralysis, or death.
Additional Reading
- Dormans JP. Establishing a standard of care for neuromonitoring during spinal deformity surgery. Spine. 2010;35(25):2180 " 2185. [View Abstract]
- Hresko MT. Clinical practice. Idiopathic scoliosis in adolescents. N Engl J Med. 2013;368(9):834 " 841. [View Abstract]
- El-Hawary R, Chukwunyerenwa C. Update on evaluation and treatment of scoliosis. Pediatr Clin North Am. 2014;61(6):1223 " 1241.
- Sponseller PD, Flynn JM, Newton PO, et al. The association of patient characteristics and spinal curve parameters with Lenke classification types. Spine. 2012;37(13):1138 " 1141. [View Abstract]
- Sucato DJ. Management of severe spinal deformity: scoliosis and kyphosis. Spine. 2010;35(25):2186 " 2192. [View Abstract]
Codes
ICD09
- 737.30 Scoliosis [and kyphoscoliosis], idiopathic
- 737.10 Kyphosis (acquired) (postural)
- 737.20 Lordosis (acquired) (postural)
- 737.32 Progressive infantile idiopathic scoliosis
- 737.31 Resolving infantile idiopathic scoliosis
- 737.9 Unspecified curvature of spine
- 754.2 Congenital musculoskeletal deformities of spine
ICD10
- M41.9 Scoliosis, unspecified
- M40.209 Unspecified kyphosis, site unspecified
- M40.56 Lordosis, unspecified, lumbar region
- M41.00 Infantile idiopathic scoliosis, site unspecified
- M41.129 Adolescent idiopathic scoliosis, site unspecified
- M40.204 Unspecified kyphosis, thoracic region
- Q67.5 Congenital deformity of spine
- M40.50 Lordosis, unspecified, site unspecified
- M41.20 Other idiopathic scoliosis, site unspecified
- M41.119 Juvenile idiopathic scoliosis, site unspecified
SNOMED
- 298382003 Scoliosis deformity of spine (disorder)
- 405773007 Kyphoscoliosis deformity of spine (disorder)
- 61960001 Lordosis deformity of spine (disorder)
- 20980008 Progressive infantile idiopathic scoliosis (disorder)
- 298493002 Kyphosis deformity of thoracic spine (disorder)
- 287087003 Congenital lordosis/scoliosis (disorder)
- 298494008 Scoliosis of thoracic spine (disorder)
- 28801006 Resolving infantile idiopathic scoliosis (disorder)
FAQ
- Q: How long do you observe a patient with spinal asymmetry before ordering a radiograph?
- A: It depends on the presence or absence of abnormalities on the physical exam. If any of the signs mentioned here are seen or significant back pain is present, a radiograph or referral is indicated. The scoliometer is also a useful tool in screening patients.
- Q: How long do you observe a patient with spinal asymmetry before referral to an orthopedic surgeon?
- A: Consider referral if
- Cobb angle
- >20 degrees
- Progression of more than 5 degrees
- Q: If a child presents with scoliosis and back pain that occurs especially at night and is promptly relieved with nonsteroidal anti-inflammatory drugs, what diagnosis is suggested?
- A: Scoliosis associated with osteoid osteoma.